Posted: 24/11/2014 at 12:02
From about June the queen just lays more eggs and then In the autumn, the eggs develop into males (drones) and fertile females. These leave the nest and mate. The fertilised females (the new queens) then hibernate until the next spring while the founder queen, the males and all the workers die and the original nest becomes deserted.
I think various factors can restrict population numbers.last year the warm spring was followed by a cold snap and was disastrous when the queens come out of hibernation too quickly. It was a wet summer the year before and it had a impact on the insects and then this affected the wasp numbers.
Unlike bees wasps are carnivorous. They hunt for other insects and if they didn’t exist, gardeners would have far more aphids and greenfly to deal with.
nature has a way of evening things out and they’ve been around for a lot longer than we have.
Edit: Matthew Oates, wildlife specialist at the National Trust says.
"They took a major hit in 2012 with that awful summer, then last year we had the coldest March on record and by the time things picked up for them in June or so it was just too late for them to recover."